Pesticide-resistant natural enemies

Definition

Populations of predatory, parasitoid, or pollinating arthropods that have evolved heritable reduced susceptibility to one or more synthetic or biological pesticides, enabling survival and continued ecosystem service provision in chemically treated agroecosystems. Resistance may arise through pre-existing genetic variation, recurrent selection pressure, or laboratory selection programs; mechanisms include metabolic detoxification, target-site insensitivity, behavioral avoidance, or sequestration. The concept is central to conservation biological control, where maintaining functional natural enemy populations alongside chemical pest suppression requires compatibility between pesticide chemistry, application timing, and the resistance status of key beneficial species.

Etymology

From pesticide (French, from Latin pestis 'plague' + Latin caedere 'to kill') + resistant (Latin re- 'back' + sistere 'to stand') + natural enemies (translation of ecological term for organisms that prey upon or parasitize pest species)

Example

Strains of the predatory mite Phytoseiulus persimilis selected for resistance to organophosphates are commercially reared and released in European greenhouses, allowing compatible use of selective acaricides against spider mites while preserving biological control services.

Synonyms

• tolerant natural enemies
• resistant beneficials

Related Terms

• Integrated Pest Management
• Conservation biological control
• insecticide resistance
• selective toxicity
• refuge strategy
• predator–prey dynamics
• sublethal effects

Usage Notes

Distinguish from 'pesticide tolerance,' which may describe transient physiological acclimation rather than heritable resistance. The term is typically applied to arthropod natural enemies (insects, mites, spiders) rather than microbial or vertebrate biocontrol agents. Resistance in natural enemies is often lower than in their pest prey, creating a 'trophic mismatch' that disrupts biological control. Some IPM programs deliberately select or screen for resistant natural enemy strains to maintain ecosystem services in high-pesticide environments.